Engine pre-oiling apparatus



Dec. 4, 1962 D. J. MONEW ETAL ENGINE PRE-0ILING APPARATUS Filed May 25,1960 3 Sheets-Sheet l Dec. 4, 1962 D. J. MCNEW ETAL ENGINE PRE-OILINGAPPARATUS 3 Sheets-Sheet 2 Filed May 25, 1960 mmm m m mm m m Y B Dec- 4,1 D. J. M NEW ETAL ENGINE PREP-OILING APPARATUS 3 Sheets-Sheet 3 Filed y25, 1960 T ll].

hired S The invention described herein may be manufactured and used byor for the government for governmental purposes without the payment ofany royalty thereon.

This invention relates to apparatus for supplying heated lubricating oilunder pressure to an engine before the engine is started and forcirculating the heated oil through the engine hearings to free thebearings for easy starting of the engine. Although this invention may beused with a variety of internal combustion engines, it is particularlyvaluable for use with an aircraft engine of the dry sump type. Furtherdescription and illustration of the invention will be with reference tothis type engine.

in cold weather operation, an aircraft engine that has been allowed tostand until its temperature has substantially equalized with theatmospheric temperature develops such extreme resistance to operativemovement of its parts that it frequently cannot be started until it hasbeen supplied internally with heated lubricating oil to free itsbearings and free the pistons in the corresponding cylinders. In view ofthis condition, such aircraft engines are provided with a pro-oilingplug or tap through which a supply of heated oil under pressure can bedelivered to the interior of the engine to flow through the workingparts of the engine to the engine oil sump. The present invention dealswith improved apparatus for heating lubricating oil and circulating suchheated oil under pressure through an internal combustion engine tocondition the engine for starting in cold weather operation.

A more complete understanding of the invention may be obtained byreferring to the following description and claims taken in conjunctionwtih the accompanying drawings which show an illustrative embodiment ofthe construction forming the basis of the invention and in which:

FIG. 1 is a side elevation view of the apparatus;

FIG. 2 is a partial, cut-away, top view of the tank portion of theapparatus;

FIG. 3 is a side elevation view in detail of the oil pressure controlvalve of the apparatus;

PEG. 4 is a top view of the apparatus;

FIG. 5 is a partial, cut-away, side elevation View in detail of thethermostatic control device;

PEG. 6 is a cut-away, partial, top view of an alternate form of theapparatus; and

PEG. 7 is a partial, side elevation view of an alternate form of theapparatus.

The apparatus, as shown in the accompanying drawings, comprises an oiltank or reservoir ltl mounted on a wheel carried platform 11. Theplatform may conveniently be supported on a pair of spaced apart wheels12 at the rear end of the device and on a single, swivelly mounted wheel13 at the front end. A tongue 14 may be connected to the pivotal supportof wheel 13 for towing the pre-oiler device to and from appropriatelocations for operation.

Tank ill is of elongated shape with flat sides and semicylindrical endsand is provided with a cover including a fixed cover portion 15 and ahinged, movable cover portion 16 through which the oil in the tank canbe replenished.

A small, preferably one cylinder, internal combustion engine 18 ismounted on the supporting platform 11 (PISS. l and 4-) at a locationspaced forwardly from the front end of tank 10, and this engine hm itsdrive are harem t shaft 19 connected through flexible coupling means 20with an oil pump 21 disposed Within tank 10 and located near the bottomof the tank. The engine has an exhaust conduit 22 which leads to atwo-way valve 23 disposed outside of the tank and adjacent the front endthereof. A conduit 24 leads from valve 23 to an oil heating coil 25which extends around the interior of tank 10 and is disposed on oradjacent to the bottom of the tank. This coil may have one or morepasses around the interior of the tank in order to provide ample heatconducting surface area, and is vented at its end opposite thatconnected to the conduit 24 by a conduit 26 which extends from the endof the coil through the front wall of the tank. A vent conduit 27extends from valve 23 downwardly through platform 11, and valve 23 iseffective to pass the engine exhaust gas either through conduit 24 toheating coil 25 or through vent conduit 27 to the atmosphere.

Valve 23 is controlled automatically. In FIG. 1, control 2d and solenoid29 are mounted on the front end wall of the tank, and the thermostaticelement of the controls is responsive to the temperature of the body ofoil contained within tank 10. Details of the controls are shown in FIG.5. Control element 28 is mounted so as to be partially inserted intotank 10. The portion of element 28 which projects into the tank containsa thermostatic element connected to rod 60, the thermostatic elementbeing responsive to the temperature of the oil in the tank and of aconstruction well known in the art. When the oil in tank 10 is beingheated, mercury switch 61 is in the off position, and valve 23 closesvent 27. When the oil in the tank is heated to a predeterminedtemperature, the thermostat causes arm 62 to turn mercury switch 61 tothe on position completing the circuit through battery 56 energizingsolenoid 29 which in turn causes valve 23 to open vent 27 to theatmosphere and close conduit 24 to the heating coil.

The wall of the tank 10 is preferably constituted by spaced apart innerand outer metallic walls with the space between the inner and outerwalls filled with a suitable heat insulative material. At the locationswhere the drive coupling 2!? and the various conduits extend through thewall, the space between the inner and outer metallic Walls is preferablyfilled by a block of solid material, as indicated at 39 in FIG. 2, andsuitable packing material (not shown) is provided to prevent the escapeof oil from the interior of the tank around the drive coupling elementand the conduits.

The oil pump 21 has an outlet port 311 and a conduit 32 extends fromthis port to the housing of an oil pressure control valve 33,particularly illustrated in FIG. 3. The housing of valve 33 providesinteriorly thereof two chambers 34 and 35 separated by a transversepartition 36 having therein a pressure relief port 3 7. A valve ball 38is disposed within chamber 35 in closing relationship to port 37 and isresiliently seated in the port by compression spring 3 compressedbetween ball 38 and the adjacent end of adjusting screw 40 threadedthrough the corresponding wall of the valve housing. Pressure conduit 32leads into chamber 34 and return conduit 41 leads from chamber 35 backinto tank 10 so that any oil forced by excessive pump pressure throughthe pressure regulating valve will flow back into the tank. The tankconnected end of line 41 is preferably provided with a nozzle 49 sodirected as to agitate or move the oil in the tank to maintain uniformheating of the oil. The pressure delivered by pump 21 can be regulatedby turning adjustment screw 40 to increase or decrease the loading ofspring 39.

A manually operated cut-off valve 42 is connected at one side to chamber34 of pressure regulating valve 33 and a pressure oil supply line 43 isconnected at one end to the other side of valve 42. At its other end,supply line 43 is provided with a fitting which engages with thepre-oiling plug or fitting 44 on aircraft engine 45. An oil return line46 is detachably connected at one end to a.

plugor fitting in the bottom of engine oil sump 47 and is connected atits opposite end to fitting 48 which leads through the fixed top portion15 of the oil tank to the interior of the tank so that the oil forcedthrough the engine and flowing into-the engine oil sump will be returnedto tank 10 for reheating and resupply to the engine. Since thepre-oiling apparatus will normally be disposed below the engine,the'return flow of oil may be accomplished at least partly by gravity.

In the use of the pre-oiling apparatus, starting from a cold conditionvalve 42 will be closed and preferably adjusting screw 40 will be movedto substantially relieve thepressure provided by pressure regulatingvalve 33. Engine 18 is then started, and, since the oil in tank lit iscold, control 28 will operate valve 23 to connect engine exhaust conduit22 with heating coil 25 in oil storage tank 10. As soon as the oil inthe tank has been heated to a sufiicient temperature, control 28 willoperate valve 23 to connect engine exhaust 22 to vent conduit 27 whichwill notify the operator that the temperature of the oil is suflicient.Adjusting screw 4% will then be turned until the proper oil pressure isobtained, as indicated on a suitable pressure gauge, not illustrated.The conduits 43 and 46 are then connected to the engine preoilingfitting44 and engine oil sump 47, respectively, and valve 42 is opened.The heated oil will now be forced through engine 45 and returned to oilstorage tank 10. If the temperature of the oil now falls below thetemperature for which control 28 is set, this control will operate valve23 to again connect the engine exhaust conduit to oil heating coils 25to supply additional heat to the oil. Operation of the pre-oiler iscontinued until the associated aircraft engine becomes sufficiently freefor easy starting, at which time valve 42 is closed and conduits 43 and46 disconnected from the engine.

In the modified arrangement shown in FIGS. 6 and 7, the construction issubstantially identical with that shown in FIGS. 1 to inclusive anddescribed above except that, in the modified arrangement, an electricmotor 50 is used to drive the oil pump 21 and electric heating elements52 are provided in. the bottom of the tank in lieu of the heating coil25.

The electric motor 50 is positioned adjacent the front end of tank 10and firmly mounted on platform 11, and this motor has its drive shaftconnected through a suitable drive coupling 51 with oil pump 21. Asuitable manually operated switch 55 is provided for controlling theenergization of the motor and the supply of heating current to heatingelements 52 and 53 mounted in the bottom portion of tank 10. Control 28,instead of controlling valve 23, controls a switch 54 which regulatesthe supply of heating current to heating elements 52 and 53 so thatheating current Will be supplied when the device is in operation and thetemperature of the oil in storage tank 10 is below the temperature forwhich control 28 is set. The modified form of the device is used in thesame manner as the first described form, the main difference being thatthe modified form can be used only in locations where suitable electricpower is available While the engine driven form can be used insubstantially any location.

We claim:

1. An engine pre-oiling apparatus comprising, in combination, areservoir for containing lubricating oil, an internal combustion enginehaving an exhaust conduit having a vent, a coil within said reservoirconnected to said exhaust conduit for receiving hot exhaust gases fromsaid internal combustion engine for heating the oil, a valve selectivelydirecting exhaust gas from said engine to said coil or said vent,and'means responsive to the temperature of oil in said reservoircontrolling said valve to regulate the supply ofexhaust gas to saidcoil, and means ii driven by said engine supplying and circulating theoil between said reservoir and an engine being pre-oiled.

2. A pre-oiling apparatus for a dry sump engine comprising a mobilesupport, a heat insulated tank mounted on said support and constitutingan oil reservoir, a pump having an inlet within said reservoir and anoutlet outside of said reservoir, a power plant carried by said supportand drivingly connected to said pump, flexible conduit means extendingfrom the outlet of said pump for conmeeting the pump outlet to the oilinlet port of an engine, flexible conduit means extending from said tankfor connecting the interior of said tank to an engine oil sump, oilheating means disposed within said tank, and control means responsive tothe temperature of the oil Within said tank to discontinue operation ofsaid oil heating means whenever the oil in said tank is heated to apredetermined temperature, said control means comprising anelectromagnetic device effective to interrupt the flow of heating mediumto said tank, and a switch responsive to the temperature of the oil insaid tank and connected to said electromagnetic device for energizingand de-energizing said device.

3. A pre-oiling apparatus for a dry sump engine independent of thenormally provided engine lubricating oil comprising a mobile support, aheat insulated tank mounted on said support and constituting an oilreservoir, a pump having an inlet within said tank and an outlet outsideof said tank, an adjustable pressure regulating valve connected to thepump outlet and having a pressure outlet and a pressure relief outlet,conduit means connecting the pressure relief outlet to the interior ofsaid tank and including a nozzle disposed within said tank for directingpressure relief oil flowing therethrough in a direction to causecirculation of the oil in said tank; a manually operated cut-off valveconnected to said pressure regulating valve and eflective when closed toreturn all of the oil delivered by said pump through said pressurerelief valve and back to said tank for circulating the oil in the tankwhile such oil is being heated, a flexible oil pressure conduitextending from said cut-on? valve for connection to an engine oil inletport, a flexible oil return conduit extending from said tank forconnecting an engine sump to saidtank, oil heating means in said tank,and means responsive to the temperature of the oil in said tankcontrolling said oil heating means to maintain the temperature of oil insaid tank at a preselected value.

4. A unitary, self-supported pre-oiling apparatus for treating differentdry sump aircraft engines with preheated lubricating oil or enginepickling fluid comprising a mobile support, a tank mounted on saidsupport constituting a reservoir for lubricating oil or pickling fluid,heating means in said tank, means responsive to the temperature of thecontents of said tank controlling said heating means to maintain thetemperature of said contents at a preselected value, a pump carried bysaid support and having an inlet connected to the interior of said tankand an outlet outside of said tank, an adjustable pressure regulatingvalve connected to the outlet of said pump, a pump driving power plantcarried by said support, an adjustable cut-off valve connected to theoutlet of said pressure regulating valve, a flexible pressure conduitconnected at one end to the outlet of said cut-off valve and adapted tobe connected at its other end to the pre-oiiing inlet port of an engineto be treated, and a return conduit connected at one end to the interiorof said tank and adapted to be connected at its other end to the oilsump of an engine to be treated.

5. A unitary self-supported apparatus for pre-oiling aircraft enginesprior to starting such engines in cold weather comprising a mobilesupport, a tank carried by said support constituting a lubricating oilreservoir, a pressure pump having an inlet connected with the interiorof said tank and an outlet, a pressure relief valve connected to theoutlet of said pump and having a pressure outlet and a vent outletconnected to the interior of said tank in a manner to create circulationof the oil in said tank, conduit means connected to the pressure outletof said relief valve and adapted to be connected to the oil inlet portsof engines to be pre-oiled, conduit means connected to the interior ofsaid tank for returning oil from engines being pre-oiled to said tank, apump driving power plant carried by said support, and thermostaticallycontrolled oil heating means in said tank.

6. A unitary self-supported pre-oiling apparatus for treating dry sumpaircraft engines with preheated lubricating oil prior to starting theengines comprising a mobile support, a tank carried by said supportconstituting a lubricating oil reservoir, oil heating means in said tankcomprising a tubular coil, a pump having an inlet connected to theinterior of said tank and an outlet adapted to be connected to thepre-oiling inlet ports of engines to be treated, a pump driving internalcombustion engine carried by said support, means including a valveeffective to connect the exhaust of said pump driving engine to saidtubular coil or to vent the engine exhaust to atmosphere, meansresponsive to the temperature of the contents of said tank controllingsaid valve to maintain the contents of said tank at a preselectedtemperature While said pump driving engine is in operation, and conduitmeans connected to the interior of said tank and adapted to be connectedto the oil sumps of engines to be treated for returning oil to saidtank.

7. An engine pre-oiling apparatus comprising, in combination, areservoir for containing lubricating oil, an internal combustion enginehaving an exhaust conduit, a heating coil within said reservoirconnected to said exhaust conduit for receiving hot exhaust gases fromsaid internal combustion engine for heating the oil in said reservoir,an actuator responsive to the temperature of the oil in said reservoir,a source of electrical energy, a solenoid connected to said source ofelectrical energy and energized by said actuator, a valve interposedbetween said exhaust conduit and said heating coil and having aplurality of passages, and means connecting said solenoid to said valveto selectively connect said passages for directing exhaust gas throughsaid heating coil or for discharging exhaust gas to the atmospherebefore entering said coil to thereby control the heating of the oil insaid reservoir by hot exhaust gases passing through said heating oil.

References Cited in the file of this patent UNITED STATES PATENTS2,388,523 Buechel Nov. 6, 1945 2,665,772 Greer et a1 Jan. 12, 19542,685,347 Busby Aug. 3, 1954 2,820,528 Harper Jan. 21, 1958 FOREIGNPATENTS 688,072 France May 6, 1930 939,809 France Apr. 26, 1948 510,659Great Britain Aug. 4, 1939 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent N0a 3,066,664 December 4, 1962 Daniel Joseph McNew eta1,

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

In the heading to the printed specification, lines 3 to 5, for "DanielJoseph McNew, Rte, 1, Box 414C, Enterprise, Ala. and Emory FredSheffield, 140 Hermitage Road, Newport News, Va." read Daniel JosephMcNew, Rte, 2, Enterprise, Ala, and Emory Fred Sheffield, 146 HermitageRoad, Newport News Va.a

Signed and sealed this 2nd day of April 1963.,

(SEAL) Attest:

ESTON Go JOHNSON DAVID L. LADD Attesting Officer Commissioner of Patents

